Parallel Generator Grounding

[GBCheeseman]

Currently working on a job with (3) 500kW generators paralleled to feed one 2400A tap box. The tap box feeds (1) 2000A ATS for building power, (1) 200A ATS for fire pump, & one (1) 100A ATS for life safety. Each generator feeds the tap box via an 800A breaker. My question is in regards to the equipment grounding conductor. Any reason to go larger than a 1/0 Cu. GND for each of the feeds from generator to tap box?

 

[Rock86]

Table 250.122.

I'm assuming you're Voltage is 480. So if you're coming from each generator with load capacity over 600A but under 800A, I shouldn't see a reason to go over #1/0 Cu.

 

[GBCheeseman]

480V, correct. Just double checking as this is not a set up I come across often.

 

[mrsmith55!]

With 1300 amps available, why are they limiting each gen to 800 amps? Just curious.

 

[mbrooke]

Do you have a single line? IS the paralleling built into the generator itself?